4_subsp. broteroana Schwarz 1936
Actually, it could be a hybrid between Q. robur and Q. petraea.
young twig often with simple hairs, becoming glabrous; bud 3-4 mm, most
often without stipules, with scales hairless or ciliate near apex; leaves
rather leathery, with 3-7 obtuse lobes, shiny dark green above, paler
below, both sides hairless; apex obtuse; base rounded, often auricled;
5-6 vein pairs, without sinusal ones; short petiole; large male and
female catkins; acorn 2-4 cm long; large cup (18-23 mm in diameter),
with broad scales (3-5 mm wide), not connate, and with narrow, subacute
apex; grows in the North and the Center of the Iberian Peninsula.

4_ var. salicifolia
= Q. robur 'Salicifolia'
petiole rather large (some autors consider it is a variety of Q.
petraea...); the leaves of young plants are often slightly lobed,
but those of mature trees are always entire; acorns give true variety
(so, some authors think it may be a subspecies...?)